Harvest timing and technique

• Chickpeas have traditionally been harvested after wheat. This practice needs to change, as the costs of delaying chickpea harvest may be considerable.
• Yield losses are due to pod drop as weathering weakens the hinge attaching the pod to the stem.
• Weathered pods become more difficult to thresh, resulting in grain loss in unthreshed pods out the back of the header, cracked grain and a slower harvest.
• Increased lodging - the risk is higher if the crop is high yielding and has been planted on wide rows.
• Harvesting at 8% moisture instead of 13% results in a harvest weight loss equivalent to $25/tonne. Farmer experience has shown yield losses of up to 30% if harvest is delayed 2-4 weeks.
• Weathered or drier grain is more likely to crack when handled, increasing the amount of split grain in the sample. The number of unthreshed pods in the sample will increase, as they become harder to thresh with weathering. Both of these can result in rejection or the need for grading to meet market requirements.
• The germination rate and vigour of planting seed will be reduced by weathering. Crops intended for seed are best harvested at 14-16% moisture and dried or aerated back to 12% moisture to maximise both germination and vigour.
• Chickpea grain discolours and darkens with weathering, reducing its desirability, particularly in the container market.
• Chickpea prices can reach peaks during harvest to meet shipping schedules. Earlier harvesting may allow access to these opportunities.
• Darker, weathered seed may be discriminated against in the market.
• Ascochyta can infect senescing pods under wet conditions, leading to infected and discoloured seed.
• Late harvested crops, particularly where there is regrowth, can be a major source of heliothis migration into neighbouring summer crops.

Harvesting tips and tools

Header modifications and settings

Draper Fronts (i.e. MacDon or Honeybee) have become increasingly popular. The centre feed draper platform provides uniform crop flow into the header, with minimal crop loss, and little damage to the seed. The cutter bar design allows for both vertical and end table flotation. While their contour following ability is not quite as good as a floating cutterbar, they have performed very well, provided the paddock is relatively level. Operators claim they can be operated at higher travel speeds than a conventional front in chickpeas.

Preferred air front setups

Air fronts help to reduce shattering losses, and minimise the amount of soil and other debris (stubble, sticks) in the final sample. Where soil contamination is likely to be a problem, fit perforated screens to replace the feeder house floor, elevator doors, and clean grain cross augers. Twin blowers may be necessary on fronts wider than 7.6 metres.

Harvest-Aire or other air fronts are generally considered better than batt reels as they minimise the risk of pods detaching from the plant. They improve feed-in over the knife section, reduce soil, sticks, rocks and stubble contamination, and allow the operator a clearer view of the cutting platform. Adjustment of the angle and height of the air nozzles is critical, and may need adjustment as crop conditions change.

Fitting a Vibra-Mat improves the flow of material over the knife-section and along the platform. They are relatively cheap with a low maintenance cost. Fit cast, short crop fingers, and if using a closed-front, the fingers will need to be spaced 19 mm or more apart. Fitting double density Kwik-cut knife guards will help reduce plant vibration and reduce the risk of pods detaching from the plant. Do not use in an un-desiccated crop and/or if there is a lot of green weed present as jamming will occur.

Check that the header front is level, and not higher at one end than the other. Set the knife at the correct angle for short crops, and install a simple depth gauge.

In short crops where soil contamination is likely to be a problem, fit perforated screens under the platform auger and/or broad elevator. Fit screens to repeat and clean-grain cross augers. Floating or flexible cutterbars can be useful in short crops.